An arbitrary number (3 x 108 - 1 x 1010/cm2) of edge dislocations on (1¯1•0) prismatic planes, with a Burgers vector of (a/3)[11•0] and with the dislocation lines nearly parallel to [00•1], were introduced intentionally into wurtzite ZnO bulk single crystals at 923 to 1073K, and the optical properties were examined. After the introduction of the dislocations, the intensity of the intrinsic emissions existing in pre-dislocated crystals, i.e., near-band edge emissions and deep-level emissions, was almost unchanged, and donor-acceptor pair emissions with photon energies of 2.20 and 2.50eV at temperature of 12K appeared. The intensity of the donor-acceptor pair emissions increased with increasing the dislocation density. The origin of the donor-acceptor pair emissions was determined as acceptor levels of 0.9 and 1.2eV depth introduced with the dislocations.

Optical Properties of Edge Dislocations on (1¯100) Prismatic Planes in Wurtzite ZnO Introduced at Elevated Temperatures. Ohno, Y., Tokumoto, Y., Yonenaga, I., Fujii, K., Yao, T.: Journal of Applied Physics, 2012, 111[11], 113514